Electropneumatic brake apparatus.



E. H. DEWSON 8: W. V. TURNER. ELEOTROPNBUMATIC BRAKE APPARATUS.APPLICATION FILED MAY 9,1910.

1,092,141 Patented Apr. 7, 1914A 3 SHEETS-"SHEET 1.

INVENTORS E. H. DEWvSON & W. VJTURNBR. ELEGTROPNBUMATIG BRAKE APPARATUS.

\ APPLICATION FILED MAY 9,1910v Att' y.

Patented Apr. 7, 191 1 3 SHEETSSHEET 2.

E H. DEWSON & W. V. TURNER.

ELEOTROPNEUMATIG BRAKE APPARATUS.

, APPLICATION FILED MAY 9, 1910.

3 SHEETS-SHEET 3.

3 v ii ilii Patented Apr. 7,

UNITED STATES rm: Fries.

EDWARD H. DEWSON, OF NEW YORK, N. Y., AND WALTER V. TURNER, 0F EDGEWOOD,PENNSYLVANIA, ASSIGNORS TO. THE WESTINGHOUSE AIR BRAKE COMPANY, OFPITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

Specification of Letters Patent.

Patented Apr. 7, 1914.

Application filed May 9, 1910. Serial No. 560,172,

To all whom it may concern:

Be it known that we, EDwAR H. Dawson and WALTER V. TURNER, citizens ofthe United States, residents of New York, in the a Anotherobject of ourinvention is toprovide means adapted to be operated both electricallyand pneumatically for locally venting air from the train pipe, so as toeffect a simultaneous application of the brakes throughout the train.

In the accompanying drawings, Figure 1 is a diagrammatic view of anelectro-pneumatic brake equipment for a motor car and trailer, wit-h ourimprovements applied thereto; Fig. 2 a central sectional view of anelectrically controlled vent valve device embodying our invention; Fig.3 a plan view of the rotary valve seat of the brake valve employed inconnection with the electro-pneumatic brake apparatus, showing therelative location of the ports and cavities; Fig. 4 a face view of therotary valve of said brake valve; Fig. 5 a diagramshowing the brakeswitch contacts developed; Fig. 6 a central sectional view illustratinga modified con- ".struction embodying our improvement; and

"LL-{modified construction embodying our in- Figs. 7 and 8 sectionalviews of still another vention.

, ratus also includes on both the motor car and the trailer a brakecylinder 8, triple yalve device 9, auxiliary reservoir 10, having pipe11, and supplemental reservoir 12 hav- 1ng pipe 13 leading to the triplevalve bracket 14. For the electric brake control preferably anapplication magnet 15 is provided which is adapted when energized toadmit air from the auxiliary reservoir 10 through pipe 16 to pipe 17,connected to the exhaust port of the triple valve 9, a release magnet 18being also provided which is adapted when deenergized to open the pipe17 to the atmosphere. Contacts are provided in the brake switch portionof the combined brake valve and switch 3 so thatin release position thecircuits are all open and both the application and the release magnetsare deenerglzed, thus closing the supply and opening the exhaust. tion,a contact finger 19, shown in the diagram Fig. 5, and leading to asource of current, engages a segment 20 of the switch drum and a contactfinger 21 is in contact with a segment 22. The contact finger 21 isconnected by a wire 23 with a train wire 24 leading to one terminal ofthe release magnet 18. Thus in electric lap position the release magnet18 is energized and the electric release valve is closed. In electricapplication position, a contact finger 25 connected to wire 26, leadingto train wire 27 of the application magnet 15, is in contact with asegment 28, so that the application magnets throughout the train areenergized to open the electric supply valves and admit fluid underpressure from the auxiliary reservoir 10 to the brake cylinder, therelease magnets being still energized to maintain the electric exhaustvalves closed. According to our invention the application and releasemagnets have one terminal permanently connected to ground and current issupplied from the head car to the magnets by the bus lines 24 and 27,suitable resistances being interposed in the conpections to the magnets,-so as..to limit the current sup- In electric lap posiv plied thereto.By this means, the voltage on each car at the 'r nagnets issubstantially uniform, regardlessf'of the length of the train, and thusa more uniform and reliable action of the magnets is obtained. For

pneumatically controlling the brakes thebrake valve seat may be providedwith a centr al port 90 connected to the train pipe branch pipe 2, anexhaust port 91 leading to the exhaust pipe 86 and a cavity 92. The

rotary valve 93 of the brake valve is provided with a central portopening 94 connected by a cavity in the valve with a large port opening95 and small port openings 96. A through port 97 is also provided in thevalve. In release position, the port 95 and through port 97 registerwith cavity 92 so as to supply air to the train pipe at the standardpressure carried in the system. In electric application and electric lappositions, the above connection remains the same, so that the train pipepressure may be maintained. In service application position the smallports 96 register with the exhaust cavity 91, so that fluid may bevented from the train pipe to effect a service application of i thebrakes, while in emergency position the larger port 95 registers withthe exhaust cavity 91, so as to effect a sudden reduction in train pipepressure and a consequent emergency application of the brakes.

As shown in Fig. 2, the electro-pneumat1c vent valve device may comprisea casing having a piston chamber containin a piston 32, the chamber 31on one side 0 the piston being normally open to the train pipe through apassage 33 containing a check valve 34, and passage 35 leading to pipe36, which is connected to the train pipe. The piston is subject on itsopposite face to the pressure of a chamber 37 which is preferablyconnected through a passage 38 with a small reservoir 39, so as toincrease the volume of the chamber. Triple valve branch pipe 40 opensinto the passage 35 and thus communicates with the train pipe. Thepiston 32 carries a valve 41 adapted to control communication forventing fluid from passage 35 and the train pipe to a pipe 42 openinginto a chamber 43 of a pneumatic switch casing 44. Mounted within thepiston 32 is a piston 45 for controlling communication from the passage33 to chamber 31. A passage 46 leads from the chamber 31 to anelectro-magnet valve device 47 having a valve 48 adapted to controlcommunication from the passage 46 to an atmospheric exhaust port 49. Thevalve 48 is normally held closed by a spring 50 and is adaptedto beopened by the movement of the armature 51 of an electro-magnet 52. Inthe switch casing 44 is a piston chamber 53 containing a piston 54having a piston stem 55 carrying a movable switch contact 56. One fixedswitch contact 59 is connected by a wire 57 with a train wire 58, thelatter wire being connected to one terminal of the vent valve magnet 52,and the other fixed contact 60 is connected to ground, so that when theswitch is closed the line wire 58 and the magnets 52 are grounded. Aspring 6.1 acts on the piston 54 to normally maintain the switch open.The other terminal of the magnet 52 is connected by a wire 62'toa sourceof current, such as the third rail or trolley, Preferably on each car, asuitable resistance 64 being interposed 1n the wire. When the brakesystem is charged ber 31, and the piston 32 being in its outer position,air flows through a feed groove 65 around the piston, charging thechamber 37 and reservoir 39 to the normal. pressure carried in thesystem. The circuit of the magnet 52 is normally open and the valve 48is held closed by the spring 50, but upon closing the circuit, thearmature 51 opens the valve 48 and air is vented from chamber 31 throughpassage 46 to exhaust port 49. The higher pressure in chamber 37thereupon shifts the piston 32 to its inner seat opening the valve 41.Fluid from the train pipe then flows through passages 35 and 42 tochamber 43 of the switch device 44 and thence through a passage 66 tothe upper side of piston 54. Said piston is thus shifted to cause theswitch contact 56 to close the circuit across the terminals 59 and 60,so that the train wire 58'is grounded and all the magnets 52 arethereupon energized. In the closed position of the piston 54, a port 67is open'to the space above the piston, so that fluid from the train pipecan escape to an atmospheric exhaust port 68. Upon a predeterminedreduction in train pipe pressure by venting to the exhaust port 68, thespring 61 shifts the piston 54 upwardly, opening the circuit across theterminals 59 and 60. The magnets 52 being thereupon dee'nergized, thevalves 48 are closed, and as the piston 32 is seated, with the feedgroove 65 closed, fluid pressure is bottled up in chamber 37. Thepressure on the opposite side of piston 32 continues to reduce by flowfrom chamber 31 past check valve 34 to vent passage 42, an exhaust port99 opening to passage 66 providing for the release of air when the port68 is cut on, until the pressure of the chamber 37 acting on adifferential area 69 of the piston 45, communication being provided tosaid area by way of ports 70, to: gether with the train pipe pressureacting within the seated area of said piston 45, is sufficient toovercome the train pipe pressure acting on the outer face of piston 45,then the piston 45 moves from its upper seat, and exposing the full areathereof to the higher pressure of the chamber 37, .is instantly seateddownwardly, so as to cut off communication from the train pipe passage33 to chamber 31. It will be noted that a restricted passage 71 isprovided through the stem 72 of the piston 32, so that the pressure offluid flowing from the passage 35 to the passage 42 is supplied to thechamber within the piston 45.-

The piston 45 being seated downwardly, communication is .opened fromchamber 37 wearer through ports 'and the restricted port 71 to passage42, so that the pressure in chamber 37 now reduces with the train: pipepressure, while the pressure in chamber 31 is bottled up. It willtherefore be evident that as soon as the pressure in chamber 37 reducesa certain amount, the pressure in chamber 31 will exceed the pressurein: charaber 37 andthe piston 32 will thereupon be shifted upwardly toclose the valve 41, and F cut off the further flow of airfrom the train:pipe. The pressure in the chamber within piston 45 then rapidly drops toatmospheric pressure by flow to the passage 42 and exhaust port 99, andthe pressure acting" on the lower exposed face of the piston 45 thereupon shifts the piston to its upper seat. it will now be evident thatthe vent valve device operates to effect a predetermined reduction intrain pipe pressure, the reduction depending upon the relativeproportioning of the parts, so that all the triple valves in the trainare caused to operate practically simultaneously to produce an emergencyapplication of the brakes.

One of the important features of our invention is that the simultaneousaction of all the vent valves in the train may be efi'ected by theaction of any one vent valve pneumatic-ally, as by a sudden reduction intrain pipe pressure initiated at some point in the train, for exampleupon a break-.in-two, or upon making an emergency reduction in trainpipe pressure at the head end of the train by means of the brake valve,the venting of fluid under pressure from chamber 31 being then throughpassages 33 and 35. The operation of a single vent valve anywhere in thetrain closes a corresponding switch 56 and thus completes the circuitfor all the magnets 52 in the train so that all vent valves are causedto operate. The circuit of .the magnets 52 may be closed in variousways, as by means of a conductors switch 7 3 on the car, adapted toconnect the line wire 58 to ground, or by providing a contact in thebrake switch adapted in emergency position to connect the wire 58 toground. As an additional safeguard, means may be provided in some cases,whereby the vent valve is operated by the breaking of a normally closedcircuit, for example, a magnet 75 havin an armature 76 for controllingavalve 7 may have a pip-e connection 78 to the passage 46, the openingof the valve 77 being adapted to .vent air from passage 46 and chamber31 to an exhaust port 79. The circuit for magnet 75 is preferablyarranged with a wire 80 on the head car connected to a source of currentand one terminal of the magnet 75 and a wire 81 connected to the otherterminal and extending through the train and including the magnets 75 onthe other cars of the train. Qnthe last car the wire 81 is connected tothe red-'1 maground; It is thus seen that the magnets 75 are maintainednormally energized and the .nets 75are operated and air is vented fromthe vent valve pistons 32 to effect a sudden reduction in train pipepressure and an 1 emergency application of the brakes;

In addition to the contacts, hereinbefore enumerated, a contact finger29, connected to the vent valve controlling magnet wire 58, may beprovided. in the brake switch, which is adapted in the emergencyposition of the brake valve to engage a segment 85- connected to ground,sothat the-movement of the brake valve to emergency position operates toground the vent valve magnets and thereby cause the simultaneousoperation. of all the vent valves in the train. Instead of an additionalcontact in the brake switch, the action of the vent valves may beinitiated by connecting the usual exhaust pipe 86 oi the brake valvewith the chamber 43 of the vent valve switch on the head car, so that inemergency position, air exhausted from the train pipe is vented tochamber 43 and thereby the switch 56 on the head car is actuated toground the vent valve circuit for the train and in this manner effectthe simultaneous action of all the vent valves. A concluctors switch 73may also be provided on each car having a wire 88 connected to the wire58 and adapted upon operation to connect the wire 58 to ground so as toset the vent valves into act-ion. If the switch 44 is connected to theexhaust pipe 86 of the brake valve, the exhaust of air from the trainpipe in making service applications of the brakes is provided for by theport 99, which is made of sutlicient size for that purpose. Thus thepiston 54 will only be actuated when a sudden reduction in train pipepressure is made.

Any type of triple valve may be employed in connection with ourimprovements but preferably we provide a triple valve of the quickaction type and utilize the usual quick action parts for supplying fluidto the brake cylinderfrom the supplemental reservoir 12 in emergencyapplications, For this purpose, the usual train pipe connection to thequick action check valve chamber is closed and said chamber is connectedby a pipe 89 to t e supplemental reservoir pipe 13, so that uponoperation of the emergency piston ii an emergency application, fluidfrom the supplemental reservoir. is supplied to the brake cylinder.

In Fig. 6 of the drawings is illustrated a modified construction inwhich the electric switch device is adapted to be operated directly bythe movement of the triple valve parts. As shown in the drawings, atriple valve device is provided, comprising the ice . graduating stem106 carrying a projecting contact member 107 which is adapted to engagespring contact clips 108 when the graduating stem is moved out by thetriple valve piston upon an emergency application of the rakes. Thecontact clips 108 are connected to a conducting member 109 which passesthrough a suitable insulating block 110 and is connected in turn to atrain wire 111 leading to one terminal of an electro-magnet 112.. Theelectro-magnet 112 is preferably carried by the cap 105 and is adaptedto operate a pair ofoppositely seating check valves 113 and 114. Thecheck valve 113 7 controls communication from a passage 115 leading tothe triple piston chamber to atmospheric ports 116 and the check valve114 controls communication from the train pipe passage 104 to passage115. The other terminal of the magnet 112 is connected to a train wire117 which leads to a suitable source of current. Normally the magnet 112is deenergized and spring 118 maintains the check valve'113 closed andthe check valve 114 open so that fluid from the train pipe may besupplied to and released from the triple valve piston chamber throughthe passages 104 and 115. When a triple valve device is moved toemergency position by a sudden reduction in train pipe pressure, the

-triple piston 101 moves out and causes the contact member 107 to engagethe clips 108. The wire 11'1is thus grounded through the triple valveand a circuit is established from the source of current throughthemagnets 112 of all the triple valves in the train, causing the magnetsto be energized andthereby the check valve 114 is shifted to closecommunication from the passage115 to the passage 104 andthe check valve113 is opened, so that fluid under pressure is ventedfrom the tri levalve piston chamber. It will now be evi ent that all of the triplevalves in the train equipped with this improvement are simultaneouslyoperated upon movement of any one triple valve to emergency position toeffect an emergency application of the brakes.

In Figs. 7 and 8 another modification is shown, in which the switchdevice is directly operated by the movement of the vent valve parts.While we have shown a vent valve device in this connection which issimilar to that shown in Fig. 2, it will be evident that the switchdevice may be employed with various other forms of vent valves. Asshown,

the valve stem 41 of the vent. valve device carries a projecting stem118 adapted to extend up into a switch cap 119 and is provided at itsouter extremity with a contact disk 120 secured to a block 121 ofinsulating material, the block 121 being movably mounted on the stem 118and having a spring 122 tending to yieldingly hold. the block inposition, so as to permit of such relative. movement as may be necessaryto compensate for any difference in movement required to bringthecontact disk 120 ,into

engagement with the fixed contacts 123 as compared with the movement ofthe. vent valve piston 32. As in the other forms of our invention one ofthe contacts 123 is connected to a source of current and the other toground. In connection with the arrangement shown in Fig. 7, aconstruction for venting air from the tri le valve piston chamber may beemploye similar to that shown in Fig. 6, but preferably we provide asomewhat difi'erent arrangement such as that shown in Fig. 8 in which acheck valve 124 is provided which is adapted to be operated by anelectro-magnet similar to the electro-magnet 112. The check'valve 124controls communication from the passage 125 opening into the. triplevalve piston chamber 126 to an atmospheric exhaust port 127. Acheckvalve 128* having a small port 129 therein controls communicationfrom the train pipe passage 104 to the passage 125. The check valve 128is for the purpose of substantially cutting off communication from thetrain pipe to the triple valvepiston chamber, so that upon operation ofthe vent valve, only fluid from the triple valve piston chamber isvented to the atmosphere, the small port 129 being rovided to permit ofsupplying air from t e train pipe to the triple valve piston chamber.

In operation, it will now be clear that upon closing the circuit of theelectro-magnets governing the valves 124 by the operation of a switch120, the vent valves 124 are opened and fluid under pressure is ventedfrom the triple valve chamber of each triple valve, thereby causing asimultaneous application of the brakes throughout the train.

It will be evident that in the various forms of our invention the ventvalves throughout the train are simultaneously operated by the action ofan electric switch upon an emergency application of the brakes or asudden reduction in train pipe pressure.

Having now described our invention, what we claim as new and deslre tosecure by Letters Patent, 1s

1. In-a fluid pressure brake, the combinastrumental in effecting areduction in fluid pressure on said valve device, and an electric switchdevice governed by said vent valve mechanism for controlling the circuitof said electrically controlled means.

2. In a fluid pressure brake, the combination with a train pipe and atriple valve op- I erated by a reduction in train pipe pressure forapplying the brakes, of av vent valve mechanism operated by a suddenreduction" in train pipe pressure for opening a ventto the train pipe,electrically controlled means for effecting a reduction in fluidjpressureon.

the triple valve to operate the 'same,fl'and. an}.

electric switch operated by saidgvent valve.

mechanism for controlling the circuit of fsaidj electrically controlled,means. I

3. The combination vwith an automatic valve device operating upon areduction in train pipe pressure for effecting an applicas tion of thebrakes, of a vent valve mechanism adapted to locally vent the train pipeelecvalve means Y for locallyf, venting" eifecting the operation of saidvalve means,

and an electric switch device directly op ated by said valve. means. forcontrolling circuit of said electrically controlled means.

-5. Ina fluid ress'ur'eibrake, the combinationwith a' bra e, cylinder,i,train.jpipe, and v "hetr'ain "of electrically f controlled jmeans- [forP v efi dgting thef'operation of} said "valve "means, I, nd i i c icwithi vi s m h n ca y connected to s"aid ]va 1ve means for -"controlid lectrically.controlled? 6.1 11 a' fluidvpressure brakeythe ,combinajtionwith a"train pipe, of a plurality of brake {equipments connected tothe train pipe, each ,cornprisingfa triple valve brake cylinder,

valve mea s-far venting fluld from the triple valvel piston,electrically controlled means for o p'eratin saidvalve means, and aswitch forljcontrollmg the electric circuit of the electricallycontrolled means, said switch being'adapted to be operated upon a suddenreduction in train pipe pressure.

' In testimony whereof we have hereunto set our hands.

EDWARD H. DEWSON. WALTER V. TURNER.

WitneS'sesi WM. M. Cour,

A. M. CLEMENTs.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. 0.

